Graphene domain signature of raman spectra of sp2 amorphous carbons

The standard D-G-2D pattern of Raman spectra of sp2 amorphous carbons is considered from the viewpoint of graphene domains presenting their basic structure units (BSUs) in terms of molecular spectroscopy. The molecular approximation allows connecting the characteristic D-G doublet spectra image of one-phonon spectra with a considerable dispersion of the C=C bond lengths within graphene domains, governed by size, heteroatom necklace of BSUs as well as BSUs packing. The interpretation of 2D two-phonon spectra reveals a particular role of electrical anharmonicity in the spectra formation and attributes this effect to a high degree of the electron density delocalization in graphene domains. A size-stimulated transition from molecular to quasi-particle phonon consideration of Raman spectra was experimentally traced, which allowed evaluation of a free path of optical phonons in graphene crystal. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Авторы
Sheka E.F. 1 , Golubev Y.A.2 , Popova N.A. 1
Журнал
Издательство
MDPI AG
Номер выпуска
10
Язык
Английский
Страницы
1-22
Статус
Опубликовано
Номер
2021
Том
10
Год
2020
Организации
  • 1 Institute of Physical Researches and Technologies, Peoples’ Friendship University of Russia (RUDN University), Miklukho-Maklaya 6, Moscow, 117198, Russian Federation
  • 2 Yushkin’s Institute of Geology, Komi Science Center, Ural Branch of RAS, Pervomayskaya 54, Syktyvkar, 167982, Russian Federation
Ключевые слова
Amorphics with molecular structure; Electrical anharmonicity; Graphene domains; One-phonon and two-phonon Raman spectra; Sp2 amorphous carbons
Дата создания
02.11.2020
Дата изменения
02.11.2020
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/64358/
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